They Just Don't Get It!

So the SiL had the baby today and they just don't get it!
My parents have turned themselves inside out to be there and be as "supportive" as they can, even though for all accounts it has seemed that they were unwanted!
Please don't think I am angry at my brother and his wife for having a baby or the baby for that matter. Somewhere deep down inside I am excited for them, I think it is wonderful...but right now I just can not be happy, I just can not!!
I wish my parents understood that I can not be a part of it, I don't want to see the pictures, I don't want to go to the hospital, I don't want to arrange things for them. I don't want to be part of it! However I have spent my day answering calls, emails and text messages about what has gone on. I know they are excited...I know they are, but I am not!
My eyes sting, from crying and all I want to do it hold my girls. I want Adison and Lillian here! I want to take them to meet there new cousin! I don't want it to be this way...why does it have to be this way? Why can't life be fair? And why can't my family accept the fact that I am not ready for this? I know it is here and I have been doing my best to prepare for it for weeks, but I am not! I do not know how to be!